Saying he was seriously injured when police horses were used unconstitutionally and unprofessionally against demonstrators outside the October 2008, presidential debate at Hofstra University, a West Virginia man has filed a federal lawsuit against Nassau County, the county police department and the department's mounted unit.

Nicholas Morgan, 26, an Iraq war veteran and a member of Iraq Veterans Against the War, says in the lawsuit filed in federal court in Central Islip that he initially was hit by one of the horses when officers were "spinning . . . and backing their horses into the crowd" of antiIraqterans Against the War, says in the lawsuit filed in federal court in Central Islip that he initially was hit by one of the horses when officers were "spinning . . . and backing their horses into the crowd" of anti-Iraq war protesters on Oct. 15, 2008. After officers on foot then knocked him to the ground, he says, that horse stepped on his head.

As a result, Morgan says in court papers, he suffered "severe and permanent physical injuries," including a crushed cheekbone, a shattered lower eye socket and a broken nose, and that he continues to have blurry vision and facial pain.

County attorneys say the mounted unit did not act illegally at the demonstration, and that the police horse unit is highly trained and was used "meticulously" in reasonably controlling illegal gatherings.

Morgan, who was a heavy construction equipment operator stationed in Baghdad from February 2004 to February 2005, says he was dressed in Army fatigues outside the event - which featured Sens. John McCain and Barack Obama - and was part of a peaceful demonstration. His lawsuit asks for $75,000 in compensatory damages, an unspecified amount of punitive damages and an order barring the county from using the mounted unit to push into crowds unless there is an extreme emergency.

Morgan could not be reached yesterday to comment. His attorney, Jonathan Moore of Manhattan, said his client is in Colorado, enrolled in a program aimed at training veterans in forestry.

"A horse is unpredictable . . . a deadly weapon," Moore said in an interview.

In court papers, County Attorney Lorna Goodman and Deputy County Attorney Matthew Weinick disagreed, saying not every injury "incurred at the hands of the police is sufficient to rise to the level of a constitutional violation." The mounted police acted professionally, they said.

The federal court test of a constitutional violation, such as Morgan alleges, requires conduct "so arbitrary and capricious that it violates the 'decencies of civilized conduct . . . so brutal and offensive that it does not comport with traditional ideas of fair play and decency,' " the attorneys for the county wrote in seeking to dismiss Morgan's suit.